Cephalosporins are a group of antibiotics derived from the fungus Cephalosporium. The first cephalosporin was discovered in 1948. They have a bicyclic molecular structure containing a beta-lactam ring. Cephalosporins are classified into generations based on their spectrum of activity, with later generations having broader spectra. They work by inhibiting bacterial cell wall synthesis. Common indications include UTIs, respiratory infections, and surgical prophylaxis. Side effects include allergic reactions and nephrotoxicity. Resistance can develop through beta-lactamase production or alterations in penicillin-binding proteins. Cephalosporins are commonly used oral and parenteral antibiotics with broad spectrums
- β-Lactam antibiotics include penicillins, cephalosporins, carbapenems, and monobactams. They contain a β-lactam ring structure and inhibit bacterial cell wall synthesis.
- Penicillins were the first discovered from the mold Penicillium and include natural penicillin G as well as semi-synthetic derivatives like ampicillin. Cephalosporins were later derived from the fungus Cephalosporium and have greater gram-negative spectrum.
- Carbapenems like imipenem and meropenem have a very broad spectrum including Pseudomonas aeruginosa resistance to most β-lactamases. Monobactams such as aztre
Aminoglycosides are a class of antibiotics that are produced by soil bacteria. They are primarily used to treat infections caused by aerobic gram-negative bacteria and some are used for mycobacterial infections. Aminoglycosides work by binding to bacterial ribosomes which interferes with protein synthesis. They have concentration-dependent bactericidal activity against many gram-negative organisms but limited activity against gram-positive bacteria. Common adverse effects include ototoxicity and nephrotoxicity. Therapeutic drug monitoring is important when using aminoglycosides to minimize toxicity risks.
Penicillins- Mechanism of action, Antimicrobial spectrum & Antibacterial resi...ANUSHA SHAJI
Penicillins are a class of beta-lactam antibiotics that were the first antibiotics used clinically in 1941. Their mechanism of action involves inhibiting the final step of bacterial cell wall synthesis by binding to and inactivating penicillin-binding proteins. This prevents cross-linking of peptidoglycan chains, leading to cell lysis as the cell wall breaks down from autolytic enzymes and osmotic pressure. Penicillin G has a narrow spectrum, being effective against gram-positive cocci like streptococci and some gram-negative cocci, but many bacteria are inherently resistant or have developed resistance via penicillinase production. Common uses include streptococcal, pneumococcal, and meningococcal infections.
Chloramphenicol is a broad-spectrum antibiotic that was initially obtained from Streptomyces bacteria but is now produced synthetically. It inhibits bacterial protein synthesis by binding reversibly to the 50S ribosomal subunit. It is primarily bacteriostatic but can be bactericidal at high concentrations. Common adverse effects include bone marrow suppression, hypersensitivity reactions, and gray baby syndrome in neonates. It is used to treat typhoid fever, meningococcal infections, and anaerobic infections when other antibiotics cannot be used.
Penicillins are a group of antibiotics that are derived from the Penicillium mold. They work by inhibiting the final step of bacterial cell wall synthesis through binding to penicillin-binding proteins. This prevents cross-linking of peptidoglycan chains, leading to cell lysis. The first penicillin discovered was penicillin G, which is acid labile and used parenterally. Semisynthetic penicillins were later developed with better stability and absorption, including penicillinase-resistant penicillins effective against Staphylococcus. Extended-spectrum penicillins like ampicillin are also active against common gram-negative bacteria.
Cephalosporins & other β lactam antibiotics & cell wall destructorsFarazaJaved
This document summarizes cephalosporin antibiotics and other β-lactam antibiotics. It discusses the classes of cephalosporins including their history, mechanisms of action, generations, and examples within each generation. It also describes other β-lactam antibiotics such as monobactams, carbapenems, and β-lactamase inhibitors. Additionally, it covers non-β-lactam cell wall acting antibiotics including vancomycin, daptomycin, fosfomycin, polymyxins, and cycloserine. The document provides detailed information on commonly used antibiotics in each class.
Cephalosporins are a group of antibiotics derived from the fungus Cephalosporium. The first cephalosporin was discovered in 1948. They have a bicyclic molecular structure containing a beta-lactam ring. Cephalosporins are classified into generations based on their spectrum of activity, with later generations having broader spectra. They work by inhibiting bacterial cell wall synthesis. Common indications include UTIs, respiratory infections, and surgical prophylaxis. Side effects include allergic reactions and nephrotoxicity. Resistance can develop through beta-lactamase production or alterations in penicillin-binding proteins. Cephalosporins are commonly used oral and parenteral antibiotics with broad spectrums
- β-Lactam antibiotics include penicillins, cephalosporins, carbapenems, and monobactams. They contain a β-lactam ring structure and inhibit bacterial cell wall synthesis.
- Penicillins were the first discovered from the mold Penicillium and include natural penicillin G as well as semi-synthetic derivatives like ampicillin. Cephalosporins were later derived from the fungus Cephalosporium and have greater gram-negative spectrum.
- Carbapenems like imipenem and meropenem have a very broad spectrum including Pseudomonas aeruginosa resistance to most β-lactamases. Monobactams such as aztre
Aminoglycosides are a class of antibiotics that are produced by soil bacteria. They are primarily used to treat infections caused by aerobic gram-negative bacteria and some are used for mycobacterial infections. Aminoglycosides work by binding to bacterial ribosomes which interferes with protein synthesis. They have concentration-dependent bactericidal activity against many gram-negative organisms but limited activity against gram-positive bacteria. Common adverse effects include ototoxicity and nephrotoxicity. Therapeutic drug monitoring is important when using aminoglycosides to minimize toxicity risks.
Penicillins- Mechanism of action, Antimicrobial spectrum & Antibacterial resi...ANUSHA SHAJI
Penicillins are a class of beta-lactam antibiotics that were the first antibiotics used clinically in 1941. Their mechanism of action involves inhibiting the final step of bacterial cell wall synthesis by binding to and inactivating penicillin-binding proteins. This prevents cross-linking of peptidoglycan chains, leading to cell lysis as the cell wall breaks down from autolytic enzymes and osmotic pressure. Penicillin G has a narrow spectrum, being effective against gram-positive cocci like streptococci and some gram-negative cocci, but many bacteria are inherently resistant or have developed resistance via penicillinase production. Common uses include streptococcal, pneumococcal, and meningococcal infections.
Chloramphenicol is a broad-spectrum antibiotic that was initially obtained from Streptomyces bacteria but is now produced synthetically. It inhibits bacterial protein synthesis by binding reversibly to the 50S ribosomal subunit. It is primarily bacteriostatic but can be bactericidal at high concentrations. Common adverse effects include bone marrow suppression, hypersensitivity reactions, and gray baby syndrome in neonates. It is used to treat typhoid fever, meningococcal infections, and anaerobic infections when other antibiotics cannot be used.
Penicillins are a group of antibiotics that are derived from the Penicillium mold. They work by inhibiting the final step of bacterial cell wall synthesis through binding to penicillin-binding proteins. This prevents cross-linking of peptidoglycan chains, leading to cell lysis. The first penicillin discovered was penicillin G, which is acid labile and used parenterally. Semisynthetic penicillins were later developed with better stability and absorption, including penicillinase-resistant penicillins effective against Staphylococcus. Extended-spectrum penicillins like ampicillin are also active against common gram-negative bacteria.
Cephalosporins & other β lactam antibiotics & cell wall destructorsFarazaJaved
This document summarizes cephalosporin antibiotics and other β-lactam antibiotics. It discusses the classes of cephalosporins including their history, mechanisms of action, generations, and examples within each generation. It also describes other β-lactam antibiotics such as monobactams, carbapenems, and β-lactamase inhibitors. Additionally, it covers non-β-lactam cell wall acting antibiotics including vancomycin, daptomycin, fosfomycin, polymyxins, and cycloserine. The document provides detailed information on commonly used antibiotics in each class.
Chloramphenicol is a broad-spectrum antibiotic produced by Streptomyces venezuelae bacteria. It works by inhibiting bacterial protein synthesis at the ribosome. It has activity against both gram-positive and gram-negative bacteria as well as some protozoa. Chloramphenicol can cause serious and potentially fatal bone marrow suppression. As a result, it is now rarely used except for certain severe infections like meningitis and anaerobic infections. It is also used topically for eye and ear infections.
Tetracyclines slide contains full information about uses, adverse effect, marketed preparation, precaution, route of drug administration, antimicrobial spectrum, mechanism of action, pharmacokineticks and pharmacodynamics of tetracyclines. This slide is very helpful for pharmacy and pharmacology student for the study about tetracyclines.
Penicillins are beta-lactam antibiotics that were discovered in 1928 by Alexander Fleming. They work by inhibiting the final step of peptidoglycan synthesis in bacterial cell walls. There are several classes of penicillins including natural penicillins, anti-staphylococcal penicillins, and extended spectrum penicillins. They are generally well-absorbed, have varying spectra of activity, and can cause allergic reactions ranging from mild rashes to anaphylaxis. Common adverse effects include hypersensitivity reactions, neutropenia, seizures, and pseudomembranous colitis.
This document provides an overview of beta lactam antibiotics, including their structure, mode of action, examples, and mechanisms of resistance. It begins by discussing the bacterial cell wall structure and how beta lactams work by inhibiting cell wall synthesis. Major classes of beta lactams covered include penicillins, cephalosporins, carbapenems, and monobactams. Examples such as methicillin, amoxicillin, and imipenem are described. The document also discusses beta lactamase resistance and concludes with a brief overview of classification.
The document summarizes the quinolones, a class of synthetic antibacterial agents. It describes their history, chemistry, generations, mechanisms of action, resistance, pharmacokinetics, clinical uses, drug interactions, and adverse effects. Quinolones work by inhibiting bacterial DNA gyrase and topoisomerase enzymes. Later generations have broader spectra of activity against both gram-positive and gram-negative bacteria. Common side effects include nausea and potential cartilage damage in children.
Cephalosporins are a class of antibiotics derived from the fungus Cephalosporium acremonium. They were first isolated in 1948 and are chemically related to penicillins. There are several generations of cephalosporins that have been developed with expanded spectra of activity. First generation cephalosporins such as cefazolin and cephalexin are effective against gram-positive bacteria. Later generations have activity against more gram-negative bacteria with third generation drugs like cefotaxime and ceftriaxone used to treat serious infections. Cephalosporins are generally well-tolerated but can cause adverse effects like diarrhea, rash, bleeding and hypersensitivity reactions in some
Tetracyclines,Biological sources,History,Sturctures,SAR,Mechanism of action,Spectrum of activity,Important structural units and the three acidity constants in the tetracycline molucule,amphoteric nature,epimerisation, chelation with metals,toxicity and uses.
This document discusses cephalosporins, a class of beta-lactam antibiotics. It describes their history, mechanism of action, classification, uses, and adverse effects. Cephalosporins are derived from the fungus Cephalosporium and work by inhibiting bacterial cell wall synthesis. They are divided into generations based on spectrum of activity, with later generations covering more resistant organisms. Common uses include skin, respiratory, and urinary tract infections. Adverse effects can include hypersensitivity reactions and antibiotic-associated colitis. Newer agents have been developed with activity against multidrug-resistant bacteria.
Cephalosporins are a class of β-lactam antibiotics derived from fungi. They are classified into generations based on their spectrum of activity, with later generations having broader spectra. They work by binding penicillin-binding proteins. Resistance can develop via target modification or β-lactamase production. Newer generations have activity against MRSA and expanded gram-negative coverage.
Cephalosporins are a class of beta-lactam antibiotics that inhibit bacterial cell wall synthesis. They include first, second, third, fourth, and fifth generation drugs with varying spectra of coverage. They have concentration-dependent bactericidal activity and are excreted renally. Common side effects include diarrhea, rash, and nephrotoxicity. Vancomycin and polymyxins have activity against gram-positive and highly resistant gram-negative bacteria, respectively. Tetracyclines have broad-spectrum coverage including MRSA and are bacteriostatic.
Penicillin Classification, Mechanism of Action, Structure Activity Relationship, Structure of Penicillins, penicillin-binding proteins (PBPs) functional propertiesCross-linking of the peptidoglycan by transpeptidases, Cross-linking of the peptidoglycan by transpeptidases, Shape of penicillin G Penicillin SAR AcylSide Chain Modifications Instability of β-lactams to nucleophiles
Penicillinase-Resistant Penicillins Protein Binding of Penicillins
Antifungal drugs work by targeting differences between fungal and human cell membranes and metabolism. Azoles like fluconazole inhibit ergosterol synthesis while polyenes like amphotericin B bind to ergosterol in the fungal cell membrane. Topical antifungals like nystatin and tolnaftate treat superficial infections while systemic drugs like fluconazole and itraconazole treat deep infections. Common adverse effects include nausea, liver toxicity, and drug interactions. The choice of antifungal depends on the infecting organism, infection severity, and route of administration needed.
1) Aminoglycosides are polybasic amino groups linked glycosidically to aminosugar compounds. They are highly water soluble and excreted unchanged in urine.
2) They are bactericidal, inhibiting protein synthesis by binding to the 30S/50S interface of bacterial ribosomes. This causes misreading of mRNA and nonfunctional protein formation.
3) Common adverse effects include ototoxicity (hearing loss) and nephrotoxicity. Individual drugs vary in their specific toxicities.
Beta lactamase inhibitors such as clavulanic acid, sulbactam, tazobactam, and avibactam work to inhibit beta-lactamase enzymes produced by bacteria that provide resistance to beta-lactam antibiotics like penicillins. They bind to and inactivate the beta-lactamase enzymes. When combined with beta-lactam antibiotics, the inhibitors can help the antibiotics overcome resistance and be effective against infections. Common combinations include amoxicillin-clavulanic acid, piperacillin-tazobactam, and ceftazidime-avibactam which are used to treat a variety of bacterial infections.
Pharmacology of Penicllins (Beta lactam antibiotics), description of their mechanism of action, mechanism of resistance, classification, indications and adverse effects
Penicillins are a group of antibiotics derived from the Penicillium mold. Alexander Fleming discovered penicillin in 1928 after noticing bacteria-killing properties of the mold. Penicillins work by inhibiting bacterial cell wall synthesis through binding to penicillin-binding proteins. They are classified based on source, administration route, and spectrum of activity. Common side effects include diarrhea and rash. Therapeutic uses include pneumonia, meningitis, and other bacterial infections.
This document provides an overview of cephalosporins, a class of beta-lactam antibiotics. It describes their classification into four generations based on their spectrum of activity and other properties. Key points include: Cephalosporins are derived from the fungus Cephalosporium and are bactericidal by inhibiting bacterial cell wall synthesis. Their classification is based on their spectrum of activity, with later generations having increased activity against gram-negative bacteria. Common examples from each generation like cefazolin, cefuroxime, cefotaxime, and cefepime are described along with their indications, dosages, and adverse effects.
This document discusses antimalarial drugs. It begins by introducing malaria and its causative parasites. It then describes the life cycle of the malaria parasite, involving stages in both the human host and mosquito vector. The objectives and classifications of antimalarial drugs are outlined. Key drugs like chloroquine, primaquine, quinine, and artemisinins are then described in detail, including their mechanisms of action, uses, and adverse effects. Combination therapies using artemisinins are emphasized as the most effective strategy to prevent drug resistance from emerging.
Chloramphenicol is a broad-spectrum antibiotic produced by Streptomyces venezuele that was introduced in 1948. It works by binding to the 50s ribosomal subunit and inhibiting protein synthesis in bacteria. However, it can also interfere with mitochondrial protein synthesis in mammalian cells, causing serious and potentially fatal blood disorders. For this reason, chloramphenicol is now reserved for life-threatening infections like meningitis or rickettsial infections when safer alternatives cannot be used due to resistance or allergies. While effective against a wide range of bacteria, chloramphenicol's use is limited by its risk of toxicities like aplastic anemia and gray baby syndrome in neonates.
This document discusses macrolide antibiotics, including their classification, mechanism of action, mechanisms of resistance, and examples like erythromycin, clarithromycin, azithromycin, and telithromycin. Macrolides are a class of natural products consisting of a large macrocyclic lactone ring with attached deoxy sugars. They inhibit bacterial protein synthesis by binding to the 50S ribosomal subunit and blocking polypeptide chain elongation. Resistance can develop via ribosomal methylation, drug-inactivating enzymes, or efflux pumps. The macrolides discussed have similar spectra but differ in absorption, distribution, metabolism, excretion, and indications.
The document defines various terms related to antibiotics such as antimicrobials, bacteriostatic, bactericidal, and antibiotic resistance. It describes different types of antibiotics like narrow and broad spectrum and discusses minimum inhibitory concentration. It provides historical context on the discovery of penicillin and discusses the classification, mechanisms of action, uses, and development of resistance for penicillins and cephalosporins. [/SUMMARY]
Myself Gaurav Chaudhary, Assistant Professor, I.T.S. College of Pharmacy.
The Slideshare contains complete Notes of Unit-1 Medicinal Chemistry-III BP601T
It contains the Classification, stereochemistry chemical degradation, and Structure-activity relationship of Antibiotics(Penicillin, Cephalosporins, Monobactum, Aminoglycosides).
The study material is authentic.
Chloramphenicol is a broad-spectrum antibiotic produced by Streptomyces venezuelae bacteria. It works by inhibiting bacterial protein synthesis at the ribosome. It has activity against both gram-positive and gram-negative bacteria as well as some protozoa. Chloramphenicol can cause serious and potentially fatal bone marrow suppression. As a result, it is now rarely used except for certain severe infections like meningitis and anaerobic infections. It is also used topically for eye and ear infections.
Tetracyclines slide contains full information about uses, adverse effect, marketed preparation, precaution, route of drug administration, antimicrobial spectrum, mechanism of action, pharmacokineticks and pharmacodynamics of tetracyclines. This slide is very helpful for pharmacy and pharmacology student for the study about tetracyclines.
Penicillins are beta-lactam antibiotics that were discovered in 1928 by Alexander Fleming. They work by inhibiting the final step of peptidoglycan synthesis in bacterial cell walls. There are several classes of penicillins including natural penicillins, anti-staphylococcal penicillins, and extended spectrum penicillins. They are generally well-absorbed, have varying spectra of activity, and can cause allergic reactions ranging from mild rashes to anaphylaxis. Common adverse effects include hypersensitivity reactions, neutropenia, seizures, and pseudomembranous colitis.
This document provides an overview of beta lactam antibiotics, including their structure, mode of action, examples, and mechanisms of resistance. It begins by discussing the bacterial cell wall structure and how beta lactams work by inhibiting cell wall synthesis. Major classes of beta lactams covered include penicillins, cephalosporins, carbapenems, and monobactams. Examples such as methicillin, amoxicillin, and imipenem are described. The document also discusses beta lactamase resistance and concludes with a brief overview of classification.
The document summarizes the quinolones, a class of synthetic antibacterial agents. It describes their history, chemistry, generations, mechanisms of action, resistance, pharmacokinetics, clinical uses, drug interactions, and adverse effects. Quinolones work by inhibiting bacterial DNA gyrase and topoisomerase enzymes. Later generations have broader spectra of activity against both gram-positive and gram-negative bacteria. Common side effects include nausea and potential cartilage damage in children.
Cephalosporins are a class of antibiotics derived from the fungus Cephalosporium acremonium. They were first isolated in 1948 and are chemically related to penicillins. There are several generations of cephalosporins that have been developed with expanded spectra of activity. First generation cephalosporins such as cefazolin and cephalexin are effective against gram-positive bacteria. Later generations have activity against more gram-negative bacteria with third generation drugs like cefotaxime and ceftriaxone used to treat serious infections. Cephalosporins are generally well-tolerated but can cause adverse effects like diarrhea, rash, bleeding and hypersensitivity reactions in some
Tetracyclines,Biological sources,History,Sturctures,SAR,Mechanism of action,Spectrum of activity,Important structural units and the three acidity constants in the tetracycline molucule,amphoteric nature,epimerisation, chelation with metals,toxicity and uses.
This document discusses cephalosporins, a class of beta-lactam antibiotics. It describes their history, mechanism of action, classification, uses, and adverse effects. Cephalosporins are derived from the fungus Cephalosporium and work by inhibiting bacterial cell wall synthesis. They are divided into generations based on spectrum of activity, with later generations covering more resistant organisms. Common uses include skin, respiratory, and urinary tract infections. Adverse effects can include hypersensitivity reactions and antibiotic-associated colitis. Newer agents have been developed with activity against multidrug-resistant bacteria.
Cephalosporins are a class of β-lactam antibiotics derived from fungi. They are classified into generations based on their spectrum of activity, with later generations having broader spectra. They work by binding penicillin-binding proteins. Resistance can develop via target modification or β-lactamase production. Newer generations have activity against MRSA and expanded gram-negative coverage.
Cephalosporins are a class of beta-lactam antibiotics that inhibit bacterial cell wall synthesis. They include first, second, third, fourth, and fifth generation drugs with varying spectra of coverage. They have concentration-dependent bactericidal activity and are excreted renally. Common side effects include diarrhea, rash, and nephrotoxicity. Vancomycin and polymyxins have activity against gram-positive and highly resistant gram-negative bacteria, respectively. Tetracyclines have broad-spectrum coverage including MRSA and are bacteriostatic.
Penicillin Classification, Mechanism of Action, Structure Activity Relationship, Structure of Penicillins, penicillin-binding proteins (PBPs) functional propertiesCross-linking of the peptidoglycan by transpeptidases, Cross-linking of the peptidoglycan by transpeptidases, Shape of penicillin G Penicillin SAR AcylSide Chain Modifications Instability of β-lactams to nucleophiles
Penicillinase-Resistant Penicillins Protein Binding of Penicillins
Antifungal drugs work by targeting differences between fungal and human cell membranes and metabolism. Azoles like fluconazole inhibit ergosterol synthesis while polyenes like amphotericin B bind to ergosterol in the fungal cell membrane. Topical antifungals like nystatin and tolnaftate treat superficial infections while systemic drugs like fluconazole and itraconazole treat deep infections. Common adverse effects include nausea, liver toxicity, and drug interactions. The choice of antifungal depends on the infecting organism, infection severity, and route of administration needed.
1) Aminoglycosides are polybasic amino groups linked glycosidically to aminosugar compounds. They are highly water soluble and excreted unchanged in urine.
2) They are bactericidal, inhibiting protein synthesis by binding to the 30S/50S interface of bacterial ribosomes. This causes misreading of mRNA and nonfunctional protein formation.
3) Common adverse effects include ototoxicity (hearing loss) and nephrotoxicity. Individual drugs vary in their specific toxicities.
Beta lactamase inhibitors such as clavulanic acid, sulbactam, tazobactam, and avibactam work to inhibit beta-lactamase enzymes produced by bacteria that provide resistance to beta-lactam antibiotics like penicillins. They bind to and inactivate the beta-lactamase enzymes. When combined with beta-lactam antibiotics, the inhibitors can help the antibiotics overcome resistance and be effective against infections. Common combinations include amoxicillin-clavulanic acid, piperacillin-tazobactam, and ceftazidime-avibactam which are used to treat a variety of bacterial infections.
Pharmacology of Penicllins (Beta lactam antibiotics), description of their mechanism of action, mechanism of resistance, classification, indications and adverse effects
Penicillins are a group of antibiotics derived from the Penicillium mold. Alexander Fleming discovered penicillin in 1928 after noticing bacteria-killing properties of the mold. Penicillins work by inhibiting bacterial cell wall synthesis through binding to penicillin-binding proteins. They are classified based on source, administration route, and spectrum of activity. Common side effects include diarrhea and rash. Therapeutic uses include pneumonia, meningitis, and other bacterial infections.
This document provides an overview of cephalosporins, a class of beta-lactam antibiotics. It describes their classification into four generations based on their spectrum of activity and other properties. Key points include: Cephalosporins are derived from the fungus Cephalosporium and are bactericidal by inhibiting bacterial cell wall synthesis. Their classification is based on their spectrum of activity, with later generations having increased activity against gram-negative bacteria. Common examples from each generation like cefazolin, cefuroxime, cefotaxime, and cefepime are described along with their indications, dosages, and adverse effects.
This document discusses antimalarial drugs. It begins by introducing malaria and its causative parasites. It then describes the life cycle of the malaria parasite, involving stages in both the human host and mosquito vector. The objectives and classifications of antimalarial drugs are outlined. Key drugs like chloroquine, primaquine, quinine, and artemisinins are then described in detail, including their mechanisms of action, uses, and adverse effects. Combination therapies using artemisinins are emphasized as the most effective strategy to prevent drug resistance from emerging.
Chloramphenicol is a broad-spectrum antibiotic produced by Streptomyces venezuele that was introduced in 1948. It works by binding to the 50s ribosomal subunit and inhibiting protein synthesis in bacteria. However, it can also interfere with mitochondrial protein synthesis in mammalian cells, causing serious and potentially fatal blood disorders. For this reason, chloramphenicol is now reserved for life-threatening infections like meningitis or rickettsial infections when safer alternatives cannot be used due to resistance or allergies. While effective against a wide range of bacteria, chloramphenicol's use is limited by its risk of toxicities like aplastic anemia and gray baby syndrome in neonates.
This document discusses macrolide antibiotics, including their classification, mechanism of action, mechanisms of resistance, and examples like erythromycin, clarithromycin, azithromycin, and telithromycin. Macrolides are a class of natural products consisting of a large macrocyclic lactone ring with attached deoxy sugars. They inhibit bacterial protein synthesis by binding to the 50S ribosomal subunit and blocking polypeptide chain elongation. Resistance can develop via ribosomal methylation, drug-inactivating enzymes, or efflux pumps. The macrolides discussed have similar spectra but differ in absorption, distribution, metabolism, excretion, and indications.
The document defines various terms related to antibiotics such as antimicrobials, bacteriostatic, bactericidal, and antibiotic resistance. It describes different types of antibiotics like narrow and broad spectrum and discusses minimum inhibitory concentration. It provides historical context on the discovery of penicillin and discusses the classification, mechanisms of action, uses, and development of resistance for penicillins and cephalosporins. [/SUMMARY]
Myself Gaurav Chaudhary, Assistant Professor, I.T.S. College of Pharmacy.
The Slideshare contains complete Notes of Unit-1 Medicinal Chemistry-III BP601T
It contains the Classification, stereochemistry chemical degradation, and Structure-activity relationship of Antibiotics(Penicillin, Cephalosporins, Monobactum, Aminoglycosides).
The study material is authentic.
The ppt covers the following topics-
1. MICROBES
2. MICROBIAL CONTROL
2.1.Reason for microbial control
2.2.Methods of microbial control
3. ANTIBIOTIC
3.1.Definition
3.2.History of antibiotic discovery
4. MAJOR ANTIBIOTIC
4.1.PENICILLINS
4.1.1 Action , organisms and biosynthesis of penicillin
4.2.CEPHALOSPORINS
4.2.1 organism and biosynthesis
4.3.AROMATIC ANTIBIOTICS
4.4.NUCLEOSIDE ANTIBIOTICS
5. APPLICATIONS OF ANTIBIOTIC
6. SIDE EFFECTS OF ANTIBIOTIC
7. CONCLUSION
Antibiotics are chemical substances produced by microorganisms that can kill or inhibit the growth of other microorganisms at low concentrations. They are classified based on their mechanism of action and chemical structure. Major classes include beta-lactam antibiotics (penicillins, cephalosporins), aminoglycosides, tetracyclines, macrolides, and chloramphenicol. They work by inhibiting bacterial cell wall, membrane, or protein synthesis. Common side effects include diarrhea, rashes, and potential toxicity to kidney or liver.
Antibiotics are chemical substances produced by microorganisms that can kill or inhibit the growth of other microorganisms at low concentrations. They are classified based on their mechanism of action and chemical structure. Major classes include beta-lactam antibiotics (penicillins, cephalosporins), aminoglycosides, tetracyclines, macrolides, and chloramphenicol. They work by inhibiting bacterial cell wall, membrane, or protein synthesis. Common side effects include diarrhea, rashes, and potential toxicity like kidney damage or bone marrow suppression in high doses.
The document discusses the history and development of antibiotics and antimicrobial chemotherapy. It begins with the discovery of sulphonamides in 1935 and penicillin in 1928. It describes the types of antibiotics including bactericidal drugs that kill pathogens and bacteriostatic drugs that inhibit growth. The document also covers the mechanisms of action, targets, and development of resistance to antibiotics.
penicillin in dentistry (ANTIBIOTICS) - by shefali jainpradeepjain24
Penicillin was the first widely used antibiotic, discovered in 1928 by Alexander Fleming. It works by inhibiting the final step of bacterial cell wall synthesis, preventing cross-linking and leading to cell lysis. It is primarily effective against gram-positive bacteria. There are natural, semi-synthetic, and extended-spectrum forms of penicillin that differ in their spectra of activity and resistance to degradation. Penicillin works by binding to penicillin-binding proteins in bacteria and inhibiting cell wall synthesis, causing cell death.
This document defines various terms related to chemotherapy and antimicrobial drugs. It discusses how antibiotics like penicillin work by inhibiting bacterial cell wall synthesis through binding to penicillin-binding proteins (PBPs). It notes that penicillin was the first effective antibiotic discovered in 1928 by Alexander Fleming. Resistance can be intrinsic, due to properties of the bacterial species, or acquired through genetic changes. Later generations of cephalosporin antibiotics were developed with broader spectra of activity against both gram-positive and gram-negative bacteria through resistance to beta-lactamases. Fifth generation cephalosporins like ceftaroline maintain activity against methicillin-resistant Staphylococcus aureus.
The history of antibiotics began with ancient cultures unintentionally discovering that mold and fermented substances had antibacterial properties. In the late 19th century, scientists began purposefully experimenting with microbes and discovered that some molds and actinomycetes produced substances that specifically inhibited or killed bacteria. Major developments included Fleming's discovery of penicillin in 1928 and the mass production of penicillin during World War II. Since then, scientists have discovered several classes of antibiotics by isolating antibiotic-producing microorganisms or synthesizing new compounds, but bacterial resistance continues to rise due to overuse and misuse of antibiotics.
This document provides an overview of antibiotics that inhibit bacterial cell wall synthesis, specifically penicillins and cephalosporins. It defines key terms related to antibiotics and resistance. It discusses the history and discovery of penicillin. It describes the mechanisms of action, classifications, therapeutic uses and adverse effects of penicillins and cephalosporins. It also addresses resistance development to these classes of antibiotics. The document is intended to teach pharmacology students about cell wall synthesis inhibiting antibiotics.
The document discusses antibiotics and their mechanisms of action. It introduces antibiotics as drugs that treat bacterial but not viral infections. It describes the discovery of penicillin by Alexander Fleming in 1926 and its development into a treatment by Chain and Florey. The main mechanisms of antibiotic action are described as inhibition of cell wall synthesis, targeting the plasma membrane, acting as antimetabolites, inhibiting protein synthesis, and inhibiting nucleic acid functions. Specific classes of antibiotics are then discussed in more detail, including sulphonamides, beta-lactam antibiotics like penicillins and their analog synthesis, and cephalosporins.
Antibiotic sensitivity and resistance .pptx seminar 2Dr. Mitali Thamke
This document discusses antibiotic sensitivity and resistance. It covers the historical development of antibiotics, classifications of antibiotics based on chemical structure and mechanism of action, and mechanisms of antibiotic resistance. Antibiotic resistance can occur via genetic or non-genetic means, including production of enzymes that break down antibiotics, modification of antibiotic targets, and changes to cell permeability. Testing methods like disc diffusion and dilution tests are used to determine antibiotic sensitivity.
Penicillin is a group of antibiotics that were among the first effective against bacterial infections like strep and staph. Scottish scientist Alexander Fleming discovered penicillin in 1928 after noticing a mold inhibiting bacterial growth. Mass production began in the 1940s, allowing penicillin to be used widely to treat infections in World War 2 soldiers. Penicillin works by inhibiting enzymes in bacterial cell walls, disrupting their formation and killing the bacteria. While many bacteria have developed resistance, penicillin remains effective against susceptible bacteria like streptococci.
This document discusses antibiotics and provides details about penicillin. It begins with definitions of antibiotics and describes how they are classified based on their effects, the types of bacteria they target, and their structure and functions. It then focuses on penicillin, noting that it was one of the first widely used antibiotics, derived from penicillium mold. The document outlines the history of penicillin's discovery and development. It also describes penicillin's structure, mechanism of action in inhibiting bacterial cell wall synthesis, and early synthesis methods.
Introduction to Antibiotics,Classification,General Mechanism of action,Penicillin,Classification of Penicillin,Moa,Structure Activity Relationship,Uses
This document provides information on various classes of antibacterial drugs, including their mechanisms of action, pharmacokinetics, clinical uses, and side effects. It discusses penicillins, cephalosporins, carbapenems, monobactams, glycopeptides, sulfonamides, trimethoprim, tetracyclines, and chloramphenicol. It describes how these drugs interfere with bacterial cell wall synthesis, folate synthesis, or protein synthesis to exert their antibacterial effects. The complex structure of the gram-negative cell wall is also outlined, explaining some bacteria's resistance to certain antibiotics.
This document provides an overview of antibiotics, including their historical background, classification, mechanisms of action, and examples. It focuses on penicillins and their discovery by Alexander Fleming in 1928. Penicillins are beta-lactam antibiotics that work by inhibiting bacterial cell wall synthesis. They have broad applications for treating bacterial infections. The document also discusses cephalosporins, another class of beta-lactam antibiotics derived from the fungus Cephalosporium.
This document discusses antibiotics. It begins by defining antibiotics as chemical compounds that kill or inhibit the growth of bacteria. It then provides a brief history of antibiotics, noting that penicillin was the first antibiotic successfully used to treat bacterial infections. The document goes on to classify antibiotics based on their chemical structure and mechanism of action. It also discusses antibiotic resistance and appropriate antibiotic use.
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DRUG DISCOVERY
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Introduction to IR, Fundamental vibrations, Types of Vibrations, Factors affecting the vibrational freaquencies, Group frequencies, examples and applications.
Applications of Infrared spectroscopy
Identification of organic compounds,
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Qualitative analysis of functional group
Quantitative analysis
Distinction between two types of hydrogen bonding
Study of chemical reaction
Study of Keto-Enol tautomerism
Conformational analysis
Geometrical isomerism
Study of complex molecules
Detection of impurity in a compound
Identification of the organic compounds by IR
Hydrocarbons, Aromatic compounds, Alcohol, Phenols, Ethers, Aldehydes, Ketones, Esters, Acid chlorides, Anhydrides, Amides, Amines, Nitriles, Isocynates, Isothiocynates, Imines and Nitro compounds.
Introduction
Instrumentation
Sampling techniques
Group frequencies
Factors affecting group frequencies
Complementarity of IR and Raman spectroscopy
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UV spectral study of alkenes
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Nucleophilic Addition of carbonyl compounds.pptxSSR02
Nucleophilic addition is the most important reaction of carbonyls. Not just aldehydes and ketones, but also carboxylic acid derivatives in general.
Carbonyls undergo addition reactions with a large range of nucleophiles.
Comparing the relative basicity of the nucleophile and the product is extremely helpful in determining how reversible the addition reaction is. Reactions with Grignards and hydrides are irreversible. Reactions with weak bases like halides and carboxylates generally don’t happen.
Electronic effects (inductive effects, electron donation) have a large impact on reactivity.
Large groups adjacent to the carbonyl will slow the rate of reaction.
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hematic appreciation test is a psychological assessment tool used to measure an individual's appreciation and understanding of specific themes or topics. This test helps to evaluate an individual's ability to connect different ideas and concepts within a given theme, as well as their overall comprehension and interpretation skills. The results of the test can provide valuable insights into an individual's cognitive abilities, creativity, and critical thinking skills
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
Or: Beyond linear.
Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
Disclaimer: No one is perfect, so please mind that there might be mistakes and typos.
dtubbenhauer@gmail.com
Corrected slides: dtubbenhauer.com/talks.html
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Slides from talk:
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11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
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https://www.etran.rs/2024/en/home-english/
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3. HISTORY OF ANTIBIOTICS
19th Century: – Louis Pasteur & Robert Koch: Bacteria as
causative agents & recognized need to control them.
Plant extracts – Quinine (against malaria)
Toxic metals – Mercury (against syphilis) – Arsenic (Atoxyl,
against Trypanosoma)
Dyes – Trypan Blue (Ehrlich) – Prontosil (azo-dye, Domagk, 1936)
Paul Ehrlich;
Started science of chemotherapy
Systematic chemical modifications
1.INTRODUCTION TO ANTIBIOTICS
4. Penicillin- the first antibiotic – 1928
Alexander Fleming observed the killing of
staphylococci by a fungus (Penicillium notatum)
observed by others - never exploited
Florey & Chain purified it by freeze drying (1940)
Nobel prize 1945
First used in a patient: 1942 •
World War II: penicillin saved 12-15% of lives
5. Selman Waksman - Streptomycin (1943)
Active against all Gram-negatives
First antibiotic active against Mycobacterium
tuberculosis
Most severe infections were caused by
Gram-negatives and Mycobacterium
tuberculosis
Extracted from Streptomyces
20 other antibiotics, incl. neomycin,
actinomycin
6. Definition: Substance produced by a microorganism
[synthetic or semisynthetic] that is capable, in low concentrations,
of inhibiting the growth of or killing other microoganisms.
Ex; Penicillin, Cephalosporin, Tetracycline etc
ANTIBIOTIC
12. 2. PENICILLIN
In 1929, Alexander Fleming isolated penicillin from a strain of
Penicillium notatum. By 1941, benzylpenicillin could be produced
in sufficient quantity to treat several infected patients.
Clinical trials with the agent, conducted by Florey and
colleagues, were successful and during World War II,
benzylpenicillin was used to treat patients with streptococcal,
gonococcal, and treponemal infections.
Shortages of the agent continued until the late 1940s when the
production of large amounts of the drug became possible by a
deep-fermentation procedure.
13. Since then, many synthetic penicillins have been developed, but
resistance to the agents has increased.
Despite the emergence of resistance to penicillins and the
development of other classes of anti-infective agents, the
penicillins remain one of the most important anti-infective classes
of drugs well into the nineties.
Penicillin G is still the drug of choice for many types of
infections, including syphilis and certain types of endocarditis
14. The basic chemical structure of all penicillins consists of a β-
lactam ring, a thiazolidine ring, and a side chain (6-
aminopenicillanic acid).
The antibacterial activity of the penicillins lies within the β-
lactam ring.
Any alteration in this ring structure forms penicilloic acid and
the antibacterial activity of the compound is lost.
The side chain varies with each penicillin compound and
generally determines the spectrum of activity, as well as the
pharmacokinetic properties of the compound.
15. There are several natural penicillins (penicillin dihydro F, X, and K),
of which benzylpenicillin (penicillin G) is the most active and is the only
natural penicillin used clinically.
22. By binding to specific penicillin-binding proteins (PBPs) located
inside the bacterial cell wall.
Penicillin G inhibits the third and last stage of bacterial cell wall
synthesis.
Cell lysis is then mediated by bacterial cell wall autolytic
enzymes such as autolysins; penicillin G may interfere with an
autolysin inhibitor.
MECHANISM OF ACTION
23. The cephalosporin's are a class of β-lactam antibiotics originally
derived from the fungus Acremonium, which was previously
known as "Cephalosporium".
Together with cephamycins, they constitute a subgroup of β-
lactam antibiotics called cephems.
The aerobic mold which yielded cephalosporin C was found in
the sea near a sewage outfall in Su Siccu, by Cagliari harbour
in Sardinia, by the Italian pharmacologist Giuseppe Brotzu in
July 1945.
3. CEPHALOSPORIN
24.
25.
26. CEPHALOSPORIN-C
Cephalosporin C is an antibiotic of the cephalosporin class. It
was isolated from a fungus of the genus Acremonium and first
characterized in 1961.
Although not a very active antibiotic itself, synthetic analogs of
cephalosporin C, such as cefalotin, became some of the first
marketed cephalosporin antibiotic drugs.
Cephalosporin C strongly absorbs ultraviolet light, is stable to
acid, is non-toxic and has in vivo activity in mice.
27. Cephalosporin C, which has a similar structure to penicillin N,
was never commercialized.
Cephalosporin C was a lead compound for the discovery and
production of many other cephalosporins.
Cephalosporins are drugs used for some people who are
allergic to penicillin.
Cephalosporins are used to treat bacterial infections such as
respiratory tract infections, skin infections and urinary tract
infections.
When a cephalosporin or any other antibiotic is given as a
treatment, the medication should be taken for the fully prescribed
time even if symptoms disappear.
35. Cephalosporins are bactericidal and have the same mode of
action as other β-lactam antibiotics (such as penicillins), but are
less susceptible to β-lactamases.
Cephalosporins disrupt the synthesis of the peptidoglycan
layer forming the bacterial cell wall.
MODE OF ACTION
36. 4. AMINOGLYCOSIDES
Aminoglycoside is a medicinal and bacteriologic category of
traditional Gram-negative antibacterial medications that inhibit
protein synthesis and contain as a portion of the molecule an
amino-modified glycoside (sugar).
The term can also refer more generally to any organic molecule
that contains amino sugar substructures.
Aminoglycoside antibiotics display bactericidal activity against
Gram-negative aerobes and some anaerobic bacilli where
resistance has not yet arisen but generally not against Gram-
positive and anaerobic Gram-negative bacteria.
37. Streptomycin is the first-in-class aminoglycoside antibiotic. It
is derived from Streptomyces griseus and is the earliest
modern agent used against tuberculosis.
Streptomycin lacks the common 2-deoxystreptamine moiety
present in most other members of this class.
Other examples of aminoglycosides include the
deoxystreptamine-containing agents kanamycin,
tobramycin, gentamicin, and neomycin.
38.
39. STREPTOMYCIN
Streptomycin is an antibiotic medication used to treat a number
of bacterial infections, including tuberculosis, Mycobacterium
avium complex, endocarditis, brucellosis, Burkholderia infection, p
lague, tularemia, and rat bite fever.
Albert Schatz first isolated streptomycin in 1943
from Streptomyces griseus.
It is on the World Health Organization's List of Essential
Medicines.
The World Health Organization classifies it as critically important
for human medicine.
40. Streptomycin structure has been shown to be composed of the
three unit’s Streptose (I), N-methyl-L-glucosamine (II), and
Streptadine (III).
41. Medical uses of Streptomycin:
Infective endocarditis
Tuberculosis
Plague
In veterinary medicine
Tularemia
Streptomycin also is used as a pesticide, to combat the growth
of bacteria beyond human applications.
Streptomycin, in combination with penicillin, is used in a
standard antibiotic cocktail to prevent bacterial infection in cell
culture.
43. Sketch the synthesis of streptomycin from dihydrostreptomycin.
Ans:
Dihydrostreptomycin
Streptomycin
44. MECHANISM OF ACTION OF STREPTOMYCIN
Streptomycin is a protein synthesis inhibitor.
It binds to the small 16S rRNA of the 30S subunit of the
bacterial ribosome irreversibly, interfering with the binding
of formyl-methionyl-tRNA to the 30S subunit.
This leads to codon misreading, eventual inhibition of protein
synthesis and ultimately death of microbial cells through
mechanisms that are still not understood.
Speculation on this mechanism indicates that the binding of the
molecule to the 30S subunit interferes with 50S subunit
association with the mRNA strand.
45. This results in an unstable ribosomal-mRNA complex, leading to
a frameshift mutation and defective protein synthesis; leading to
cell death.
Humans have ribosomes which are structurally different from
those in bacteria, so the drug does not have this effect in human
cells.
At low concentrations, however, streptomycin only inhibits
growth of the bacteria by inducing prokaryotic ribosomes to
misread mRNA.
Streptomycin is an antibiotic that inhibits both Gram-positive and
Gram-negative bacteria, and is therefore a useful broad-spectrum
antibiotic.
46. 5. CHLOROMYCETIN (CHLORAMPHENICOL)
Chloramphenicol was discovered after being isolated
from Streptomyces venezuelae in 1947.
in 1949 a team of scientists at Parke-Davis including Mildred
Rebstock published their identification of the chemical structure
and their synthesis, making it the first antibiotic to be made
instead of extracted from a microorganism.
It is on the World Health Organization's List of Essential
Medicines. It is available as a generic medication.
Chloramphenicol is an antibiotic useful for the treatment of a
number of bacterial infections.
This includes use as an eye ointment to treat conjunctivitis.
47. By mouth or by injection into a vein, it is used to
treat meningitis, plague, cholera, and typhoid fever.
Common side effects include bone marrow suppression,
nausea, and diarrhea.
The bone marrow suppression may result in death.
Chloramphenicol is a laevorotatory compound.
CHLORAMPHENICOL
50. The tetracyclines, a large family of antibiotics, were discovered
by Benjamin Minge Duggar in 1948 as natural products, and first
prescribed in 1948.
Benjamin Duggar, working under Yellapragada
Subbarow at Lederle Laboratories, discovered the first tetracycline
antibiotic, chlortetracycline (Aureomycin), in 1945.
In 1950, Harvard University professor R.B. Woodward, in
collaboration with a group at Pfizer, determined the chemical
structure of the related substance, oxytetracycline (Terramycin).
Tetracycline was patented in 1953 and came into commercial
use in 1978.
6.TETRACYCLINE
51. It is on the World Health Organization's List of Essential
Medicines.
Tetracycline is available as a generic medication. Tetracycline
was originally made from bacteria of the Streptomyces type.
Tetracyclines have a broad spectrum of antibiotic action.
Originally, they possessed some level of bacteriostatic activity
against almost all medically relevant aerobic and
anaerobic bacterial genera, both Gram-positive and Gram-
negative.
58. MECHANISM OF ACTION
Tetracycline inhibits protein synthesis by blocking the
attachment of charged aminoacyl-tRNA to the A site on the
ribosome.
Tetracycline blocks the A-site so that aminoacyl-tRNAs can't
come in. Tetracycline binds to the 30S and 50S subunit of
microbial ribosomes.
Thus, it prevents introduction of new amino acids to the
nascent peptide chain. The action is usually inhibitory and
reversible upon withdrawal of the drug.
59. Mammalian cells are less vulnerable to the effect of
tetracyclines, despite the fact that tetracycline binds to the small
ribosomal subunit of both prokaryotes and eukaryotes (30S and
40S, respectively).
This is because bacteria actively pump tetracycline into
their cytoplasm, even against a concentration gradient, whereas
mammalian cells are simply not affected by the mechanisms of
tetracycline within the cytoplasm.
This accounts for the relatively small off-site effect of
tetracycline on human cells.